Three-dimensional printer



FIG. 1 is a front, right side perspective view of a three-dimensional printer according to our new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a left side elevation view thereof;

FIG. 5 is a right side elevation view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The dot-dash broken lines depict the bounds of the claimed design and form no part of the claimed design. All dash-dash broken lines depict portions of the three-dimensional printer that form no part of the claimed design. 

CLAIM The ornamental design for a three-dimensional printer, as shown and described. 